Flashcube construction

ABSTRACT

The flashcube has a transparent protective cube, a reflector member formed of four individual reflectors and four mechanically ignitable flashbulbs seated on the mounting plate, one each associated with a reflector. The mounting plate has four openings which are used as passage for the trigger pin coming from the camera to actuate the striker arm of a striking-mechanism spring held in prestressed position such that when the striker arm is released, it springs back to its rest position and thereby strikes the igniter in the tubulation projecting from the bulb. In accordance with the invention, the four striker arms are held in prestressed position by a metal member provided in the mounting plate; it is shaped as a plate with four flaps bent upwards at right angle, or as a cup provided with notches in the side wall.

[111 3,807,934 [451 Apr. 30, 1974 FLASHCUBE CONSTRUCTION Inventors: Josef Lukas, Augsburg; Alfred Wacker, Friedberg; Ingo Kress, Berlin, all of Germany Assignee: Patent-Treuhand-Gesellschaft fur elektrische Gluhlampen mbH, Munich, Germany Filed: Apr. 2, 1973 Appl. No.: 346,757

Foreign Application Priority Data Apr. 20, 1972 Germany 2219390 References Cited UNITED STATES PATENTS 6/1971 Beach 431/93 3,737,643 6/1973 Lukas et a]. 431/93 Primary Examiner-Carroll B. Dority, Jr.

Attorney, Agent, or Firm-Flynn & Frishauf ABSTRACT The flashcube has a transparent protective cube, a reflector member formed of four individual reflectors and four mechanically ignitable flashbulbs seated on the mounting plate, one each associated with a reflector. The mounting plate has four openings which are used as passage for the trigger pin coming from the camera to actuate the striker arm of a strikingmechanism spring held in prestressed position such that when the striker arm is released, it springs back to its rest position and thereby strikes the igniter in the tubulation projecting from the bulb. In accordance with the invention, the four striker arms are held in prestressed position by a metal member provided in the mounting plate; it is shaped as a plate with four flaps bent upwards at right angle, or as a cup provided with notches in the side wall.

6 Claims, 5 Drawing Figures PATENTEDAPR 30 I914 3.8071934 sum 2 OF 2 FIG. 30 v 3b FLASHCUBE CONSTRUCTION Cross reference to related patent application: U.S. Ser. No. l59,6l3, filed July 6, 1971, now U.S. Pat. No.

'The invention relates to a multiflash system and more particularly to a flashcube construction with four mechanically ignitable flashbulbs incorporated therein.

The flashcube is of similar design to conventional flashcubes including electrically ignitable flashbulbsv and comprises a cube-shaped, light-transmissive protective covering which encloses a reflector seated on a mounting plate. The mounting plate is externally provided with a jack holder which is designed such that the flashcube can be supported in an adapter provided therefor on the camera. Four mechanically ignitable flashbulbs are inserted in the mounting plate in a manner such that the igniter tubes projecting from the bulbs are inserted in blind holes provided therefor. Four striking mechanisms of spring shape are provided for ignition of the flashbulbs with their striker arms held in tensioned position and released for ignition by a trigger means coming from the camera, which enables, when triggered, the striker arm to spring back in its rest position and strike the igniter tube of the respective flashbulb sideways.

British Patent 1,294,370 disclose e.g. a torsion spring which functions as the aforesaid striking mechanism. This torsion spring is shaped from piano wire, has a U-shaped portion which comes to lie between the reflectors when the Specifications 1,294,369 and spring is mounted and has an arm at right angle to the U-shaped portion which is used as the striker arm. The other end of the spring is of hook shape and keeps the striker arm in the required tensioned position.

Another spring design which is suited as a striking mechanism is disclosed in U.S. Ser. No. 159,613, now U.S. Pat. No. 3,737,643. A spiral spring with several turns is mounted on a pin provided therefor in the mounting plate. One arm of the spring is designed as the striker arm; the other end of the spring is bent to hook shape to form a locking arm which keeps the striker arm in its tensioned position.

The two above described springs have in common that the striker arm is held in its tensioned position by the respective, particularly hook-shaped, design of the other spring end. In most cases the hook-shaped spring end is simultaneously used to locate the striking mechanism in position within the mounting plate. The spring thus has several functions: it serves as a striking mechanism; provides its own seating; and holds itself tensioned. This renders the shape of the spring complex. Manufacture of such springs is rather complicated; further, the complex spring design leads to substantial difficulties during mounting. It is not possible to mechani cally separate these springs, when in a bulk package, since entangling of their loops, arms, coiled and/or U- shaped portions, occurs and disentangling is only possible by hand. Disentangling by hand, however, introduces atime consuming step in the assembly of the flashcubes, which, therefore, introduces additional expense.

It is an object of the present invention to provide a flashcube having a striking mechanism which is more simple to manufacture and easy to mount.

SUBJECT MATTER OF THE PRESENT INVENTION:

A metallic member-is provided in the center of the mounting plate of the flashcube which holds the four striker arms of the striking-mechanism spring seated in the corners of the mounting plate on pins provided therefor in prestressed position. The strikingmechanism springs can be designed as simple spring clips with straight arms since a hook-shaped end for keeping the striker arm in prestressed position can now be omitted. The metallic member holding the striker arms in their tensioned position may have the form of a small plate which is positively seated and positioned by engagement with a respective recess of the mounting plate. Four flaps are bent upwards from the plate and form the respective contact surfaces for the striker arms. Instead of a plate a cup-shaped metallic member may be used which is seated in the recess. The side walls are formed with four notches, or cut-outs, the remainder of the walls providing the necessary bearing surfaces for the striker arms of the springs.

The invention will be described by way of example with reference to the accompanying drawings, wherein:

FIG. 1 is an exploded perspective view of a flashcube;

FIG. 2a is a front view, and

FIG. 2b is a side view of a holding plate;

FIG. 3a is a front view; and

FIG. 3b is a sectional view along lines A-B of FIG. 3a

of a holding cup. The flashcube shown in FIG. 1 comprises the transparent protective cube l which encloses the four-sided reflector 2. Both reflector and protective cube are seated on a mounting plate 3 which has a stop shoulder 4. Preferably, the mounting plate 3 is a plastic casting or molding and has four blind holes 5 which receive the tubes 7 projecting from the mechanically ignitable flashbulbs 6. Tube 7 contains an igniter which is ignitable by impact and causes combustion of combustible material, e.g. zirconium shreds enclosed in the flashbulb. The mounting plate 3 is provided with four openings 8 in the form of sectional annular grooves which are used as passages for a trigger pin (not shown) coming from the camera. Pins 9 are cast integrally with the corners of mounting plate 3 and one spiral spring 10, each, serves as the striking mechanism and is seated on each respective pin. Spiral spring 10 has several turns with a diameter selected so as to fit over pins 9, and has two straight arms, preferably of about equal lengths, one of which is used as the striker arm. The striker arms are held in the required tensioned position by a metallic member 11 located in the center of mounting plate 3. The mounting plate 3 has a circular recess 12 with lugs 13 for accommodation of metallic member 11 in positively seated locked engagement to be supported therein such that distortion is prevented.

As shown in FIGS. 2a and 2b, the metallic member 11 is a small, essentially square plate of sheet steel with its corners rounded off so as to fit in recess 12 and provided with recesses 14 which are in interlocking engagement with lugs 13 of mounting plate 3. At each corner a flap 15 is bent upwardly at right angle to the plate close to recesses 14. The flaps 15 keep the striker arm of the springs 10 in the required tensioned position. Their height is such that the striker arm can be lifted by the trigger pin from the camera, to slide overhead past the flaps to spring back to its rest position. The plate may have a central bore or opening 16 which affords advantages in manufacture and assembly, and prevents distortion, while decreasing the weight of the plate and use of material.

As seen in FIGS. 3a and 3b, the metallic member 11 may have the shape of a cup. The cup is deep-drawn from sheet steel; it may also have (because of manufacturing techniques) a central opening 18. Its outer diameter corresponds to recess 12 in mounting plate 3. The cup has four radial recesses 17 which are interlocked with lugs 13. The recesses 17 are continued in wall 19 so that the wall is interrupted and provides, at the side edge of the side wall 19, contact surfaces for the striker arms to hold the striker arms in tensioned position.

Various changes and modifications may be made, and features described in connection with any one embodiment may be used, within the inventive concept with other embodiments of the invention.

We claim: 1. A multiflash element comprising a transparent protective housing enclosing a multisided reflector (2), a mounting plate (3), and a plurality of mechanically ignitable flashbulbs (6) having igniter tubes (7) inserted in the mounting plate,

the mounting plate being formed with openings forming passages (8) for camera trigger means;

an ignition spring each, for each bulb, each spring having a striker arm adapted to be engaged by the camera trigger means so that, when the striker arm is released, it may spring back from tensioned position towards its rest position and thereby strike, sideways, the igniter in the tube (7) projecting from the bulb,

and means (9) holding the springs (10) in the base,

wherein the improvement comprises a metallic member (11) located in the center of the mounting plate (3) interlocked therewith, and holding the respective striker arms of the springs (10), the means holding the springs being located at the circumference of the mounting plate (3) to hold the springs, by cooperation with the plate, in tensioned condition.

2. A multiflash element according to claim 1, wherein the metallic member (11) is a plate having a plurality of upwardly bent flaps (15) extending at a right angle from the plate.

3. A multiflash element according to claim 1, wherein the metallic member is a cup formed with recesses (17) in the side wall (19).

4. A multiflash element according to claim 1, wherein the mounting plate (3) is formed with a recess (12), and has lugs (13) projecting therefrom; and the metallic member (11) holding the striker arms in tensioned position is interlocked with the recess (12) and 

1. A multiflash element comprising a transparent protective housing enclosing a multi-sided reflector (2), a mounting plate (3), and a plurality of mechanically ignitable flashbulbs (6) having igniter tubes (7) inserted in the mounting plate, the mounting plate being formed with openings forming passages (8) for camera trigger means; an ignition spring (10), each, for each bulb, each spring having a striker arm adapted to be engaged by the camera trigger means so that, when the striker arm is released, it may spring back from tensioned position towards its rest position and thereby strike, sideways, the igniter in the tube (7) projecting from the bulb, and means (9) holding the springs (10) in the base, wherein the improvement comprises a metallic member (11) located in the center of the mounting plate (3) interlocked therewith, and holding the respective striker arms of the springs (10), the means holding the springs being located at the circumference of the mounting plate (3) to hold the springs, by cooperation with the plate, in tensioned condition.
 2. A multiflash element according to claim 1, wherein the metallic member (11) is a plate having a plurality of upwardly bent flaps (15) extending at a right angle from the plate.
 3. A multiflash element according to claim 1, wherein the metallic member is a cup formed with recesses (17) in the side wall (19).
 4. A multiflash element according to claim 1, wherein the mounting plate (3) is formed with a recess (12), and has lugs (13) projecting therefrom; and the metallic member (11) holding the striker arms in tensioned position is interlocked with the recess (12) and the lugs (13) to prevent distortion.
 5. A multiflash element according to claim 1, wherein the striking-mechanism spring (10) is a spring clip with straight arms of about even lengths.
 6. A multiflash element according to claim 1, wherein the reflector has four sides, the base (3) is about square, and four springs (10) are provided; and the metallic member has four holding surfaces (15; 19), each surface engaging a striker arm of one spring (10). 